标题: 改良式水中自充填混凝土
A Modified Underwater Self-Compacting Concrete
作者: 叶峻阁
Yeh, Chun-Ko
赵文成
Jau, Wen-Chen
土木工程学系
关键字: 水中自充填混凝土;抗冲蚀;特密管;underwater self-compacting concrete;anti-washout;tremie
公开日期: 2009
摘要: 土木工程在施工过程常需要于水中浇置混凝土,诸如桥墩、基桩等,在过去多使用坍度较低、富配比之混凝土,使混凝土具有较好的工作度及黏滞性,此时工程人员最关心的是混凝土离开特密管后,水泥砂浆是否随着水流失,或者混凝土与水混合而增加水灰比导致强度因而减少。而构造物因配置钢筋量的增加,较高的钢筋用量导致间隙更密,除了增加施工的困难性,结构物的品质更是难以控制。若能将水中混凝土达到自行充填的性能且在水中不分散,便能大幅改善水中结构物的品质。
所以本研究以自充填特性和水中不分散、减少凝结时间以及增加抗压强度为实验目标,尝试用不同种类之添加试剂改善初凝、终凝时间,而实验结果对初凝时间有所提升3~4小时,终凝时间甚至提升了4~5小时;除了基本的工作性测试需符合自充填混凝土规范之外,并经过抗冲蚀试验对新拌混凝土之相关性质,达到水中不分散的要求,并在混凝土硬固后测试力学性质,在水中浇置时最高达到6000psi以上;亦测试耐久性与体积稳定性之试验以确保混凝土之品质,使得施工过程达到快速、环保,降低生态破坏,而水中结构物的品质达到安全、耐久、实用等目的,对我国在混凝土方面上的研究、创新与开发新的技术有所贡献。

关键字:水中自充填混凝土、抗冲蚀、特密管
There are many concrete structures are constructed under water, such as footings, piers, and slurry walls. In the past, rich mix design concrete were used to obtain a low slump, and high viscosity. The engineers are concerned about the mortar dispersion after the concrete is placed in water or the water was mixed with concrete which yields a higher w/c. If the concrete used in underwater condition can have the self-compacting ability, a much better quality of concrete can be expected.

This study focused on the non-dispersion, less setting time, higher strength, and self-compacting concrete. Various admixtures were tried and the test results showed that the initial setting time can be 3-4 hours less and final setting time 4-5 hours less. The anti-washout tests were also performed. The concrete placed in water showed a compressive strength at 28 days of 6000 psi. The shrinkage was also measured. Thus a new underwater self-compacting concrete was developed to guarantee the quality, safety, and economy.


Key words: underwater self-compacting concrete, anti-washout, tremie
URI: http://140.113.39.130/cdrfb3/record/nctu/#GT079616503
http://hdl.handle.net/11536/42225
显示于类别:Thesis